Closure panels such as hoods and deck lids of motor vehicles generally include an inner panel and an outer panel. The inner and outer panels are connected to each other at various locations so they cooperate to provide a structure which is more rigid than either panel separately, and which has a stiffness which is much greater than the sum of the separate stiffnesses of the panels. For hoods and deck lids, the outer panel lies above the inner panel and is part of the exterior of the vehicle. The inner panel is only visible when the hood or deck lid is open.
Typically, when a closure panel is manufactured, the inner and outer panels are formed separately. The exact shape of the outer panel is defined by the desired form of the vehicle. The inner panel is designed to mate with the outer panel. For example, there may be truncated cones formed on the inner panel. Adhesive is placed on the truncated surfaces of these cones and then the outer panel is placed over the inner panel, so the truncated surfaces of the cones are adhered to the outer panel. The perimeters of the inner and outer panels are then joined in a hemming operation. In this operation, the edge of the outer panel is bent around the edge of the inner panel.
The closure panel is generally secured in a closed position by a latch on the vehicle which engages a latch engagement member on the closure panel. The latch is on the frame or other portion of the vehicle which is not part of the closure panel. The latch engagement member may be a striker plate, or a loop of metal which is referred to as a wire loop. Generally, the latch engagement member is at the end of the closure panel which is farthest from the hinges which attach the closure panel to the vehicle.
The latch engagement member for a hood, deck lid or other closure panel is typically located on the inner panel. The latch area of the inner panel, where the latch engagement member is attached, may experience high forces due to wind loads, inertial forces, or closure forces. Also, the outer panel, in the vicinity of the latch area of the inner panel, may experience large forces due to persons pressing on the outer panel to close the hood, deck lid or other closure panel, and engage the latch. If it is not sufficiently stiff, this area may deform when it is pressed to close the panel.
It is known in the art to attach various reinforcement members to the inner panel and the outer panel to withstand these forces. In the most common arrangement, a palm area reinforcement is attached to the outer panel. For a hood or deck lid, the palm area reinforcement is attached to the underside of the outer panel. For a hood, the palm area reinforcement is attached to the outer panel at its front end. For a deck lid, the palm area reinforcement is attached at the rear end of the outer panel.
Also, for a hood or deck lid, a latch area reinforcement is usually attached to an upper surface of the inner panel. The latch area reinforcement provides added strength and stiffness to the portion of the inner panel adjacent the latch engagement member. For a hood, it is attached to the front end of the inner panel, for a deck lid, it is attached at the rear end of the inner panel.
FIG. 1 is a sketch of a prior art reinforcement assembly 10 which provides reinforcement for both the palm area and the latch area. The reinforcement assembly 10 is shown inverted in order to show details.
Reinforcement assembly 10 includes a palm area reinforcement 12 which, during assembly of the closure panel, is adhesively bonded to the palm area of the outer panel. Palm area reinforcement 12 may have grooves 14 and 15 to provide increased rigidity. Grooves 14 and 15 appear as ridges in FIG. 1 because reinforcement assembly 10 is shown inverted.
Reinforcement assembly 10 also includes a latch area reinforcement 16 which is assembled to the palm area reinforcement 12 at 18 and 19. Latch area reinforcement 16 has an opening 17 which is to be aligned with an opening on the inner panel (not shown in this figure) where the latch engagement member is mounted.
During assembly of the hood or deck lid, the assembly 10 is inverted and the latch area reinforcement 16 is attached to the inner panel, positioned so that opening 17 is aligned with the latch opening in the inner panel. Adhesive is then placed on the palm area reinforcement 12 on the side 11 which is opposite the side shown in FIG. 1. Then, when the outer panel is put in place, the palm area of the hood or deck lid is pressed down onto the surface 11 of the palm area reinforcement 12 of the reinforcement assembly 10. Typically, the adhesive on the reinforcement assembly 10 is a thermosetting adhesive. When the paint bake operation is subsequently performed on the hood or deck lid, the adhesive is cured.
In addition to the art cited above, which is standard practice in the motor vehicle industry, a number of patents relate to reinforcement in the palm and latch areas of closure panels.
U.S. Pat. No. 5,538,094 and the related patent, U.S. Pat. No. 5,535,841, teach a reinforcement member attached to both the inner and outer panels in the latch area of a car hood. The reinforcement member is elongate and has a C-shaped cross section. It is mounted transversely relative to the hood. The C-shaped member is made of a lightweight material such as aluminum or plastic.
The C-shaped member encloses a plate made of a strong material such as steel. The steel plate has a flanged hole, and the hood is secured in a closed position by a latch member which passes through the flanged hole, and engages the flange. The steel flange resists wear.
U.S. Pat. No. 6,247,744 teaches sub assemblies having self-aligning members for hinges and latches of vehicle doors, hoods or trunks. The sub assemblies may be used with vehicle hoods, trunks, liftgates and deck lids. They serve to integrate the closure member with the vehicle body.
U.S. Pat. No. 6,394,211 teaches a latch system for a hood and fender assembly on a truck.
U.S. Pat. No. 6,450,276 provides an illustration of the typical mounting of a hood latch on a front end assembly of a motor vehicle.